Investments (Tables)

3 Months Ended

Mar. 31, 2023

Investments [Abstract]

Debt Securities, Available-for-sale

	March 31, 2023								December 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Securities available-for-sale:
Obligations of states and
political subdivisions	$	247,589	$	487	$	19,202	$	228,874	$	292,293	$	346	$	24,324	$	268,315
Mortgage-backed securities:
U.S. government agencies	1,318,398		546		126,984		1,191,960		1,342,666		299		140,686		1,202,279
Private label	7,554		—		401		7,153		7,695		—		464		7,231
Trust preferred securities	4,592		—		467		4,125		4,590		—		762		3,828
Corporate securities	26,573		—		2,426		24,147		26,620		—		2,753		23,867
Total Securities Available-for-Sale	$	1,604,706	$	1,033	$	149,480	$	1,456,259	$	1,673,864	$	645	$	168,989	$	1,505,520

Gross Unrealized Losses And Fair Value Of Investments

The following table shows the gross unrealized losses and fair value of the Company’s investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (in thousands):

	March 31, 2023
	Less Than Twelve Months				Twelve Months or Greater				Total
	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
Securities available-for-sale:
Obligations of states and political subdivisions	$	42,850	$	1,084	$	155,074	$	18,118	$	197,924	$	19,202
Mortgage-backed securities:
U.S. Government agencies	318,110		24,334		582,062		102,650		900,172		126,984
Private label	7,051		401		—		—		7,051		401
Trust preferred securities	—		—		4,125		467		4,125		467
Corporate securities	10,251		755		13,896		1671		24,147		2,426
Total available-for-sale	$	378,262	$	26,574	$	755,157	$	122,906	$	1,133,419	$	149,480

	December 31, 2022
	Less Than Twelve Months				Twelve Months or Greater				Total
	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
Securities available-for-sale:
Obligations of states and political subdivisions	$	203,173	$	21,929	$	13,359	$	2,395	$	216,532	$	24,324
Mortgage-backed securities:
U.S. Government agencies	533,611		50,268		376,778		90,418		910,389		140,686
Private label	7,126		464		—		—		7,126		464
Trust preferred securities	—		—		3,828		762		3,828		762
Corporate securities	22,972		2,648		895		105		23,867		2,753
Total available-for-sale	$	766,882	$	75,309	$	394,860	$	93,680	$	1,161,742	$	168,989

Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity

The amortized cost and estimated fair value of debt securities at March 31, 2023, by contractual maturity, is shown in the following table (in thousands).  Expected maturities will differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.  Mortgage-backed securities have been allocated to their respective maturity groupings based on their contractual maturity.

	Amortized Cost		Estimated Fair Value
Available-for-Sale Debt Securities
Due in one year or less	$	32,645	$	2,108
Due after one year through five years	514,814		47,615
Due after five years through ten years	720,243		491,176
Due after ten years	337,004		915,360
Total	$	1,604,706	$	1,456,259

Gross Gains And Losses Realized

Gross gains and gross losses recognized by the Company from investment security transactions are summarized in the table below (in thousands):

	Three months ended March 31,
	2023		2022
Gross realized gains on securities sold	$	975	$	—
Gross realized losses on securities sold	(202)		—
Net investment security gains	$	773	$	—
Gross unrealized gains recognized on equity securities still held	$	463	$	7
Gross unrealized losses recognized on equity securities still held	(102)		(730)
Net unrealized gains recognized on equity securities still held	$	361	$	(723)